The present invention relates to grasping devices such as tongs used to handle food, which may be locked in a closed position for storage using a gravity-based locking means.
Spring-loaded tongs are commonly used to handle food and provide a convenient way to grasp objects to be temporarily transported. The spring is biased to urge the tongs to an open position such that they are ready for immediate use.
One problem with spring loaded tongs is that the tongs take up a significant amount of space if left in the open condition. This is typically not a problem when the tongs are used, but becomes undesirable when the tongs are to be stored. If the tongs are compressed and placed in a drawer, the spring action of the tongs may cause them to open rendering the drawer difficult to open.
Various methods have been employed to reduce the storage area required for spring loaded tongs. One method as proposed in U.S. Pat. No. 5,199,756 discloses a movable lock actuated by manually sliding a locking plate to a position where the tong arms are restricted from moving. This locking plate is engaged or disengaged by applying force to the plate, requiring the user to hold the tongs in a closed position with one hand while sliding the locking plate into an engaged or disengaged position with the other hand.
External means for retaining the tongs in a closed position may be applied such as provided by rubber bands or some other method of securing the tong arms in a closed position. These methods are less than satisfactory and may lead to the tongs springing open upon failure or dislodging of this external restraint. Rubber bands are likewise unsuitable because the rubber breaks down over time leaving residue on the utensil.
The prior art methods require the use of two hands or changing hand positions in order to affect the locking mechanism, rendering them difficult to close by people having reduced or limited functionality of a hand.
U.S. Pat. No. 4,609,132, discloses a gravity-based locking device used for hanging clothes. This hanger provides a locking mechanism that uses a cylinder placed between two angled surfaces that rides on a shaft. The mechanism used can trap clothes of variable thicknesses between the first and second arms while providing a suitable operation for a hanger. The '132 mechanism, while providing a method for a variable thickness gravity based locking mechanism does not offer a suitable mechanism for use in tongs since the tongs lock in only a fully closed position.
What is desired therefore is an improved set of tongs or grasping devices that may be operated easily by one hand, that has a simple method of locking and unlocking using gravity to actuate the locking mechanism.